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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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392                                ALASKAN GLACIER STUDIES
Ficlcett Glacier}- From the Sú00 foot divide of the through glacier of which Sherman Glacier is the western end, an ice tongue descends eastward toward the Copper River valley. This is Fickett Glacier,2 an ice tongue nearly 4 miles long and from half a mile to a mile wide. It descends over 2500 feet from snowfield to terminus and has one steeply-cascading tributary from a cirque on the southern side. It is just barely visible from the Copper River railway and we have not approached it closely.
Saddlebag Glacier. Saddlebag Glacier is a smaller, double-ended through glacier, south of Fickett Glacier. Its two members rise on a SOOO foot divide, the shorter, eastern portion having a length of 1$ miles and terminating in the Copper River valley about 900 feet above sea level, while the larger, southern portion is 3$ miles long and descends to within 200 feet of the level of the sea. This southern portion of the glacier, which I                            occupies the deep valley on the seaward face of the Chugach Mountains, between Mc-
i                            Kinley Lake and Copper River, is a third of a mile wide and is fed not only by the ice
j                            tongue from the through divide, but by a tributary from a cirque on the west.   A photo-
|                            graph by H. P. Ritter of the U. S. Coast and Geodetic Survey shows that in 1899 it was
clean and little crevassed, and had a narrow barren zone in front, and a valley train of outwash gravels, extending southward to Copper River.   Its valley walls, seen just j                           before crossing the Copper River on the first steel bridge, have been rendered very pre-
|                           cipitous by glacial erosion.   There are also small glaciers north of McKinley Lake.8
|                               Goodwin Glacier.   Goodwin Glacier, which is immediately south of Childs Glacier,
j                           has a known length of nearly 7 miles and a width in the mountain valley of three-fourths
!                           of a mile.    On emerging into Copper River valley it expands into a piedmont bulb between
:                           two and three miles in width.   It rises in cirques and snowfields 5000 to 6000 feet above
sea level on the slopes of Mt. Murchison, and slopes gradually, at an angle of 710 in the lower portion, but with no visible hanging valley relationships.   The number of tribu-;                           tariea is not known, but there are two conspicuous ones from the south, which, however,
give rise to no medial moraines. The terminus, rising about 400 feet above the river, does not form an ice cliff in Copper River as the Childs Glacier does, but the ice extends almost to the water's edge being separated only by a crescentic area of terminal moraine and outwash, most of which is thickly covered with aiders and with scattered cottonwoods. Inside this forest belt is a barren zone of moraine-covered ice, also crescentic in form, ,;                           and extending up to -the clear ice of the valley glacier, where in 1910 there were a few
i1                           reddish, moraine-covered ice cones and some grayish ablation moraine.
i                               Goodwin Glacier is a conspicuous object from portions of the Copper River and North-
|                           western Railway.   It was named by Abercrombie,4 who in 1884 camped upon a barren
i                           part of the outwash deposit, and is shown, in a general way, on his 1898 map.   This map
|j                           and the allusion by Seton KarrB to Goodwin and Childs Glaciers as ice tongues which
I                           spread out in 1886 "with beautiful fan-like shape to the river level," make it clear that
I                           the advance and expansion of the Goodwin bulb took place over 25 years ago.   The
:                                       i Named in 1910 for Ered W. Kckett, the soldier who accompanied Lieutenant Allen up the Copper River
i;                                  in 1885.
* Not Goodwin Glacier as an early map suggested.
* See map by D. C. Witherspoon, Bull. 542, U. S. Geol. Survey, 1913, PI. HI, facing p. 78.
* Abercrombie, W. E., Supplementary Expedition into the Copper River Valley, Alaska, Narratives of Ex* plorations in Alaska, Senate Rept. 1023, 56th Congress, 1st Session, Washington, 1900, p. 387.
* Seton Earr, H. W., Shores and Alps of Alaska, London, 1887, p. 170.